<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>测试1</title>
    <style>
        body{
            /*background-color: #f00;*/
            text-align: center;
            line-height: 600px;
            font-size: 150px;
        }
    </style>
</head>
<body>
多屏幕互动
<script>
    setTimeout(function () {
        document.getElementsByTagName('body')[0].style.backgroundColor = '#0f0';
    },3000)




























</script>
</body>
</html>